In Java, LinkedHashSet class contains methods known as contains() which is used to return true if this set contains the specified element otherwise false.
Syntax:
public boolean contains(Object o)
Parameters: Element o as a parameter whose presence in this set is to be tested.
Return Type: A boolean value, true if this set contains the specified element.
Example 1:
// Java program to Illustrate contains() Method
// of LinkedHashSet class
// For String value
// Importing required classes
import java.util.*;
// Main class
public class GFG {
// Main driver method
public static void main(String[] argv) throws Exception
{
// Try block to check for exceptions
try {
// Creating an empty LinkedHashSet
// Declaring object of string type
LinkedHashSet<String> linkset
= new LinkedHashSet<String>();
// Populating above HashSet
linkset.add("A");
linkset.add("B");
linkset.add("C");
// Printing all elements of above LinkedHashSet
System.out.println("LinkedHashSet: " + linkset);
// Checking the existence of element
// using contains() method
boolean exist = linkset.contains("C");
// Printing boolean value if present or not
System.out.println("Is the element"
+ " 'C' present: " + exist);
}
// Catch block to check for exceptions
catch (NullPointerException e) {
// Display message if exception occurs
System.out.println("Exception thrown : " + e);
}
}
}
Output:
LinkedHashSet: [A, B, C] Is the element 'C' present: true
Example 2:
// Java program to Illustrate contains() Method
// of LinkedHashSet class
// For Integer value
// Importing required classes
import java.util.*;
// Main class
public class GFG {
// Main driver method
public static void main(String[] argv) throws Exception
{
// Try block to check for exceptions
try {
// Creating an empty LinkedHashSet
// Declaring object of integer type
LinkedHashSet<Integer> linkset
= new LinkedHashSet<Integer>();
// Populating above HashSet
linkset.add(10);
linkset.add(20);
linkset.add(30);
// Printing all elements of above LinkedHashSet
System.out.println("LinkedHashSet: " + linkset);
// Checking the existence of element
// using contains() method
boolean exist = linkset.contains(25);
// Printing boolean value if present or not
System.out.println("Is the element"
+ " '25' present: " + exist);
}
// Catch block to check for exceptions
catch (NullPointerException e) {
// Display message if exception occurs
System.out.println("Exception thrown : " + e);
}
}
}
Output:
LinkedHashSet: [10, 20, 30] Is the element '25' present: false